Author Topic: 50mm tbi install.  (Read 3884 times)

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Offline chardrc

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Re: 50mm tbi install.
« Reply #15 on: July 13, 2011, 08:53:05 PM »
looking forward to your install the proper way.. im happier and happier with my jeep each day. keeps up with traffic, and my clutch pedal stopped being lazy.. and i filled it up again and got 17mpg 2nd time in a row. whould also note heere that since the 13mpg figure noted earlier i installed an electric fan and the correct spark plugs (previous owner thought small block Chevy plugs would work in it never sealed up right and only went half as far into the head as they needed to...)
1990 YJ 4cly, ax5, 2.5 inch BDS lift, 31 MTr\'s,  Powertrax-lockers all around, track-bars removed, boomerang shackles, warn m8000 winch, electric fan. [sold but not forgotten]

2007 jk Rubicon 2dr

Offline chardrc

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Re: 50mm tbi install.
« Reply #16 on: August 26, 2011, 04:53:22 PM »
just an update. ran 2 more tanks through the jeep and getting 17.2mpg like clock work.

 I'm going to get a rotary rasp and another gasket this weekend and open up the manifold opening and install the spacer this weekend or the beginning of next week so I have some time to drive and test it before school starts.  (should have been wheeling the jeep this weekend but that fell through  :brick: so have to  at least work on the jeep.)

Barretsyj did you ever get around to doing this mod?
1990 YJ 4cly, ax5, 2.5 inch BDS lift, 31 MTr\'s,  Powertrax-lockers all around, track-bars removed, boomerang shackles, warn m8000 winch, electric fan. [sold but not forgotten]

2007 jk Rubicon 2dr

Offline grumpygy

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Re: 50mm tbi install.
« Reply #17 on: August 26, 2011, 06:35:19 PM »
As soon as I do some repairs to the HD this weekend I too will be working on the jeep.  Header on back(complete replacement of my exhaust.).  Now I will have no excuss for not opening up the Intake to match the throttle body.
94 YJ, Cool Air intake, 19lb Inj, 4.0 Throttlebody with spacer,  31/10.50/15's

Offline chardrc

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Re: 50mm tbi install.
« Reply #18 on: January 15, 2012, 03:37:04 PM »
 I decided to take apart the idle air controller to see if it was getting gummed up and if i could get the adjustment screw to screw in more (so it could close the throttle more). I opened it up to find the grease to be quite thick after 21 years of use. After some work with the vice and penetrating fluid I got the adjustment screw to move and reduced its length from 0.22" to 0.16". then i gave it some new grease and put it back together. The actuator seems to work better now having a greater range of motion (actually fully extends when you turn it off rather than partially extending). I didn't take the jeep out on the road as I'm trying to keep it salt free but i let it run long enough to warm up in the shop and it idled down to 1k repeatedly. The tb itself seems to be jamming up as I can push the throttle closed a bit more and get it to idle at 800 rpm (where id like it to be). when i had the iac out I noticed there was some binding near closed throttle. I'm may have gotten the plate in abit off center when I had to disassemble it to get the return spring set up right (back when i installed the tb). I'll dig into that when I put the spacer on in the spring. In the mean time its closer to idling where it should for the once a month start up while in storage.
1990 YJ 4cly, ax5, 2.5 inch BDS lift, 31 MTr\'s,  Powertrax-lockers all around, track-bars removed, boomerang shackles, warn m8000 winch, electric fan. [sold but not forgotten]

2007 jk Rubicon 2dr

Offline sharpxmen

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Re: 50mm tbi install.
« Reply #19 on: January 15, 2012, 06:10:26 PM »
to center the butterfly: losen the 2 screws that hold it to the shaft just a tiny bit, unscrew the level setting screw until is not touching, open the throttle and then let it close and push with your finger on the higher edge of the butterfly (highest point as it sits at an angle), check in the light so it's not off center (should have same amount of light on both sides if any, should be almost no light at with some around the shaft), tighten the screws. At this point the butterfly will bind, lift the setting screw until it pushes it up a bit so it won`t bind, that`s your minimum setting and go from there.
'95 YJ, NSG370 6spd / Hurst shifter, Dana 300 + 4:1 Doubler / tri-stick, Custom skid, Super D35 / Auburn LSD / 4.88, 35x12.5x15 BFG KM2, 64mm t/b, 1.7 RollerRockers, MkVIII e-fan, Dual Diaph Booster
Latest: Corbeau BajaRS heated seats :dance: keeping warm the rear end

Offline chardrc

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Re: 50mm tbi install.
« Reply #20 on: January 16, 2012, 06:31:31 AM »
thanks for the instructions. 1 thing that i also think is the problem is that the new tb didn't have anything to stop the shaft from sliding in and out other than the throttle plate itself. this resulted in the tb binding if the shaft was pushed all the way to one side. in comparison the original tb had very little shaft play and never bound. I'm going to look into the original tb to see if the new one was missing something. (wont be albe to look at the jeep for a while as school starts tomorrow but the old tb is at home)
1990 YJ 4cly, ax5, 2.5 inch BDS lift, 31 MTr\'s,  Powertrax-lockers all around, track-bars removed, boomerang shackles, warn m8000 winch, electric fan. [sold but not forgotten]

2007 jk Rubicon 2dr

Offline sharpxmen

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Re: 50mm tbi install.
« Reply #21 on: January 16, 2012, 08:06:35 AM »
i don't think there's anything centering the shaft (at least on the 91-95 there isn't), problem is that if the butterfly is not centered will catch an edge into the body (it's oval shaped)
'95 YJ, NSG370 6spd / Hurst shifter, Dana 300 + 4:1 Doubler / tri-stick, Custom skid, Super D35 / Auburn LSD / 4.88, 35x12.5x15 BFG KM2, 64mm t/b, 1.7 RollerRockers, MkVIII e-fan, Dual Diaph Booster
Latest: Corbeau BajaRS heated seats :dance: keeping warm the rear end